Oxygen uptake, respiratory complexes, and metabolic activities have been studied in mitochondria isolated from the hepatopancreata of Mytilus galloprovincialis collected in the “Mar Grande” of Taranto (Ionian Sea, Italy). | Turkish Journal of Biology Turk J Biol (2013) 37: 565-572 © TÜBİTAK doi: Research Article Hepatopancreas mitochondria of Mytilus galloprovincialis: effect of zinc ions on mitochondrial bioenergetics and metabolism 1 2 2 1 Antonino DE LISI , Ermelinda PRATO , Francesca BIANDOLINO , Giulio SARLI , 1, 3 4 Donatella NEGRO *, Gianluigi LA PIANA , Domenico MARZULLI 1 Institute of Plant Genetics, National Research Council (CNR), Bari, Italy 2 Institute for Coastal Marine Environment, Section of Taranto, Taranto, Italy 3 Department of Biochemistry and Molecular Biology, University of Bari, Bari, Italy 4 Institute of Biomembranes and Bioenergetics, National Research Council (CNR), Bari, Italy Received: Accepted: Published Online: Printed: Abstract: Oxygen uptake, respiratory complexes, and metabolic activities have been studied in mitochondria isolated from the hepatopancreata of Mytilus galloprovincialis collected in the “Mar Grande” of Taranto (Ionian Sea, Italy). Although exposure to µg Zn2+/L resulted in a significant increase of states 3 and 4 respiration with glutamate + pyruvate as respiratory substrate, it was found that the exposure of mussels to different concentrations of Zn2+ (– µg/L) neither inhibited mitochondrial respiration nor exerted any inhibitory effect on representative mitochondrial dehydrogenases. It rather stimulates these activities, producing an extra synthesis of adenosine triphosphate by hepatopancreas mitochondria and possibly increasing its availability in the cytoplasmic compartment. This might be considered as a specific strategy utilized by the mussel to cope with variations in the heavy metals content of the marine environment, and it could be used to detect toxic effects. Key words: Zinc, Mytilus galloprovincialis, mitochondria, respiratory enzymes 1. Introduction Heavy metals are continually discharged into the .